DE191455C - - Google Patents

Description

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IMPERIAL

PATENT OFFICE.

PATENT LETTERING

-JVe 191455- CLASS 426th GROUP

CARL RICHTER and HEINRICH HÄSER in WITKOWITZ, Moravia.

of arc lamp coals.

Patented in the German Empire on December 13, 1906.

Recognized May 24, 1905.

The measurement of arc lamp carbon concerns the separate determination of the following Sizes:

i. the diameter,
2. the length,

3. the deviation from straightness,

4. the deviation of the cross-section from the circular shape.

With the present instrument, all these quantities can be determined separately, namely the ^length] / ₁₀ mm, the other sizes to ¹ A ₀₀ mm; the apparatus is to be used mainly when taking over deliveries of arc lamp coals.

The subject matter of the invention is shown in a side view in the accompanying drawing in FIG. 1, while FIG. 2 shows a horizontal section through the axis of the micrometer screw. The instrument consists of a millimeter ruler fastened in a vertical position on a base plate G, which serves as a guide for the upper bearing bracket T ₁ and the bracket T _{2 of} the micrometer screw gauge M at the same time. If bending of the carbon rods is not to be feared, the apparatus can also be arranged horizontally in a similar manner.

A conically adjustable bearing, in which the pins of two centering chucks Z ₁ and Z ₂ run, is inserted into both the base plate and the bearing bracket T _1. The jaws of the upper centering chuck have a larger overhang along the axis because of the non-cylindrical tip of the coal. The lower chuck carries a disc S divided into 360 degrees and the amount of its rotation can be read from the mark h firmly attached to the base plate. The centering chucks each have a precisely aligned stop surface J ₁ and f ₂ , the positions of which are set along the axis so that the graduation 400 of the millimeter ruler falls into the plane of f _x and the graduation ο of the same falls into the plane f% , if a control rod of exactly 400 mm in length is inserted into the instrument.

The screws S ₁ and ₂ serve to clamp the carbon pin in the chucks, which are dimensioned so that coals with a diameter of 5 to 30 mm can be clamped. The screw t is used to lock

of the bearing bracket T ₁ and the screw t ₂ for clamping the bracket T _{2 of} the micrometer screw gauge. The guide sleeve comprising the ruler of the latter carrier, as well as that of the carrier T _1, are provided with verniers. The guide sleeves can be moved along the ruler by hand or with endless screws.

The micrometer gauge attached to the carrier T ₂ consists of the micrometer screw m with the measuring surface r, a longitudinal scale s, a mark n connected to T ₂ , a partial cylinder t and an adjusting screw g. The cylinder t can be rotated on the spot at the same time as the tube i , while the latter moves along the scale s as it rotates and reaches its graduation ο evenly when the measuring surface r coincides with the axis AA ^{1 of} the apparatus. A recess is left on the carrier T ₂ at α in order to be able to observe the carbon surface against a light background when the measuring surface r is set. Screws J ₁ and J ₂ are adjusting screws.

With regard to the handling of the device, the following should be noted:

The light from an arc lamp is only distributed symmetrically to the lamp axis, when the carbon pins are straight. This straightness exists when the Centers of gravity of all cross-sectional areas of the pen fall into a straight line. So long If this condition is met, the cross-sections deviate from the circular shape no significant disadvantages.

Because of the different influence of these two types of shape defects on the light distribution it is important when purchasing delivered arc lamp coals to determine these two sizes separately, what by the apparatus described above is done in the following way:

The carbon rod is loosely placed between the centering chucks Z ₁ and Z ₂ and the upper support T _{1 is} pushed downward until its stop surface f _v touches the tip of the carbon. Then read off the length of the coal using the vernier attached to the carrier T _{1 on the millimeter ruler.}

Now clamp the carbon rod in the centering chuck by turning the screws S ₁ and A ₂ and rotate the same together with the chucks and the disk S until the mark h coincides with the graduation ο of the disk S.

If you want to z. B. to determine the shape of that cross-section of the coal, which has a distance of χ mm _{from the end of the same sitting on the surface / 2} , move the carrier T _{2 of} the micrometer screw gauge until the center line of this gauge with the graduation χ of the millimeter ruler coincides, which can be determined with the help of the vernier N • attached to the carrier T _2.

After tightening the screw Z ₂ , you begin to record the shape of the cross-section in question by rotating the carbon rod in sequence through various angles readable from the mark h and after each rotation of the adjusting screw g, the measuring surface r in contact with the, Brings coal surface. With each setting, the angle of rotation is read off at h as well as the distance of the relevant surface point of the carbon from the axis AA ^{1 on the micrometer gauge.}

If one plots all related angles and length measurements from a point which represents the intersection point of the axis AA ¹ with the relevant cross-section, the connecting curve of the end points of all these radial lines indicates the shape of the circumference of the measured cross-section. The application can be made on any scale, depending on the desired accuracy.

Its center of gravity can then be determined from the shape of the cross-section using known methods and its distance from the center of the beam, which, as mentioned, represents the intersection of the axis AA ¹ with the relevant cross-section, is equal to the deviation of the rod from straightness at the relevant point . If the cross-section in question were circular, λπππ the smallest, X _max the largest reading on the micrometer screw gauge, then the measure of the deviation from straightness for this cross-section would be the value

o, =

obtain.

By examining different cross-sections in the same way, a maximum value a _max is obtained for this deviation, which represents the arrow height of the entire curvature of the rod and which, in the case of good coals, must not exceed a certain amount. In the case of a circular cross-section, the diameter of the coal is generally d = X _max - \ - X _m ; _n , and in the particular case where its center falls on axis AA ¹ , where X _max = X _m i _n = λ, then d - 2 \ ..

As a measure of the deviation of a cross-section from the circular shape, the difference A = R - r of the radius of the same circumscribed and inscribed circles is to be considered

strive, which have the center of gravity of that cross-section as the common center. If ρ is the radius of a circle with the same area as a cross-sectional area F, so is

p = ² π = F or ρ = I / _-:,

so are the absolute amounts of the deviations upwards and downwards

the sum of which again results in Δ.

If the deviation of the cross-sections from the circular shape is small, a complete recording of the same is not necessary, but it is sufficient _{to determine X max} and X _m i "and to calculate α from them.

For checking purposes, every device is provided with a steel rod that has been precisely turned into a circular cylinder 400 mm long and 20 mm in diameter.

The check of the correspondence of the graduation line ο on the millimeter ruler with the stop surface / ₂ is carried out by an applied adjustment ruler.

Claims (1)

Patent claim: Instrument for measuring the length, diameter and curvature of arc lamp coals, characterized in that a centering chuck (Z ₂ ) provided with circular graduation (S ) and a millimeter ruler (R) are fastened in a vertical position on a base plate (G), to which the upper centering chuck (Z ₁ ) and a carrier (T ₂ ) arranged between the centering chucks (Z ₁ Z _% ) for a micrometer screw gauge (M) can be locked. 1 sheet of drawings.